Shoes By Firebug LLC v. Stride Rite Children's Grp., LLC

962 F.3d 1362

SHOES BY FIREBUG LLC, Appellant

v.STRIDE RITE CHILDREN'S GROUP, LLC, Appellee

2019-1622, 2019-1623

United States Court of Appeals, Federal Circuit.

Decided: June 25, 2020

William Alciati, Gardella Grace PA, Washington, DC, for appellant.

Gaetan Gerville-Reache, Warner Norcross & Judd LLP, Grand Rapids, MI, for appellee. Also represented by Robert Michael Azzi.

Before Lourie, Moore, and O'Malley, Circuit Judges.

Lourie, Circuit Judge.

Shoes by Firebug LLC ("Firebug") appeals from two final written decisions of the United States Patent and Trademark Office Patent Trial and Appeal Board ("the Board") holding claims 1–10 of U.S. Patent 8,992,038 (" ’038 patent") and claims 1–10 of U.S. Patent 9,301,574 (" ’574 patent") unpatentable as obvious. See Stride Rite Children's Grp., LLC v. Shoes by Firebug LLC , No. IPR2017-01809, 2019 WL 236242 (P.T.A.B. Jan. 16, 2019) (" -1809 Decision "); Stride Rite Children's Grp., LLC v. Shoes By Firebug LLC , No. IPR2017-01810, 2019 WL 237069 (P.T.A.B. Jan. 16, 2019) (" -1810 Decision "). Because the Board did not err in its conclusion that the claims would have been obvious over the prior art, we affirm.

BACKGROUND

Firebug owns the ’038 and ’574 patents (collectively the "Firebug patents"), which are generally directed to illumination systems for footwear. ’038 patent col. 1 ll. 10–12.¹ According to the patents, while light-up shoes are not new to the footwear industry, there is a wide variety of structural designs for illuminated footwear. In some designs, the light sources are external to the footwear, while in others the lights are integrated into the shoes. The Firebug patents purport to disclose an improved structure for internally illuminated footwear. The patents describe footwear comprising a sole and an upper portion having three layers—a liner, which is the innermost layer, an interfacing layer, and a light-diffusing layer. Id . col. 2 l. 45–col. 3 l. 8. The light sources are connected to the interfacing layer between the interfacing layer and the light diffusing layer. Id . col. 2 l. 65–col. 3 l. 1. The interfacing layer is a reflective layer that maximizes the amount of light that exits through the light-diffusing layer and is ultimately visible to an observer. Id . col. 3 ll. 3–5. Claim 1 of the ’038 patent is illustrative:

1. An internally illuminated textile footwear comprises:

a footwear ;

the footwear comprises a sole and an upper;

an illumination system;

the illumination system comprises a power source and a plurality of illumination sources;

a liner;

a structure;

the structure comprises an interfacing layer and a batting;

the structure being adjacently connected to the upper;

the structure being positioned between the liner and the upper;

the interfacing layer being positioned adjacent to the liner;

the batting being adjacently connected to the interfacing layer opposite the liner;

the interfacing layer being reflective;

the batting being light diffusing;

the plurality of illumination sources being adjacently connected to the interfacing layer;

the plurality of illumination sources being positioned between the interfacing layer and the batting;

the upper being perimetrically connected to the sole;

the liner being positioned interior to the upper;

the upper being light diffusing;

the illumination system being housed within the footwear;

the plurality of illumination sources emitting light, wherein the light first entering the batting and being diffused by the batting, the light diffused by the batting exits the batting, enters the upper, diffused again by the upper and then exits the upper, the twice diffused light creating a visual impression of internal radiant illumination across an outer surface area of the upper.

’038 patent col. 7 ll. 26–57 (emphasis added).

Claim 1 of the ’574 patent recites similar subject matter, with slight differences relevant to this appeal.

1. An internally illuminated textile footwear comprises:

a sole and an upper;

an illumination system;

the illumination system comprises a power source and a plurality of illumination sources;

a liner;

an interfacing layer;

the interfacing layer being adjacently connected to the upper;

the interfacing layer being positioned between the liner and the upper;

the plurality of illumination sources being adjacently connected to the interfacing layer;

the plurality of illumination sources being positioned between the interfacing layer and the upper;

the upper being perimetrically connected to the sole;

the liner being positioned interior to the upper;

the upper being a light diffusing section;

the illumination system being housed within the footwear ; and

the plurality of illumination sources emitting light, wherein the light enters the light diffusing section, then exits the upper as diffused light, creating a visual impression of internal radiant illumination across an outer surface of the upper.

’574 patent col. 9 l. 47–col. 10 l. 5 (emphasis added).

Stride Rite Children's Group, LLC ("Stride Rite") is a competitor to Firebug in the children's footwear market. Firebug asserted the ’038 and ’574 patents against Stride Rite in the United States District Court for the Eastern District of Texas. See Complaint, Shoes by Firebug LLC v. Stride Rite Children's Grp., LLC , No. 4:16-cv-00899 (E.D. Tex. Nov. 22, 2016), ECF No. 1. Stride Rite in response filed petitions for inter partes review of claims 1–10 of the ’038 patent and claims 1–10 of the ’574 patent, alleging that the challenged claims would have been obvious over U.S. Patent 5,894,686 ("Parker") in view of U.S. Patent App. Pub. 2011/0271558 ("Rosko") and other references.

Parker teaches a light distribution system for use on the upper portion of a shoe and discloses a layer of woven or non-woven optical fibers disposed on a "back reflector," which reflects light from the optical fibers back through the outer layer of the shoe. Parker, col. 4 ll. 18–34. Rosko discloses a multi-layered lighting panel for footwear that uses an array of light-emitting diodes disposed in a "light diffuser" for illumination. Rosko ¶ 23. Stride Rite contended that the challenged claims would have been obvious because a skilled artisan would have substituted Parker's fragile optical fiber layer with Rosko's LED-based light diffuser to reduce cost and improve the structural integrity of the footwear.

The Board instituted trial on both petitions and issued a final written decision in each proceeding concluding that the challenged claims are unpatentable as obvious. In both decisions, the Board determined that the preamble of claim 1 of each of the Firebug patents, which is the only independent claim at issue in each IPR, does not limit the challenged claims. -1809 Decision , 2019 WL 236242, at *6 ; -1810 Decision , 2019 WL 237069, at *8. The Board concluded that the references otherwise render the challenged claims obvious and the disclosure of the references is not outweighed by Firebug's evidence of secondary considerations of nonobviousness. -1809 Decision at *23–24 ; -1810 Decision at *24.

Firebug timely appealed the Board's decisions. We have jurisdiction under 28 U.S.C. § 1295(a)(4)(A).

DISCUSSION

Firebug presents two principal arguments on appeal. First, it argues that the Board erred in determining that the preambles of claim 1 of both the ’038 and ’574 patents do not limit the claims. Second, it argues that the Board erred in concluding that the challenged claims would have been obvious in light of the prior art and Firebug's evidence of secondary considerations of nonobviousness. We address Firebug's arguments in turn.

I. Claim Construction

"Claim construction is a question of law that may involve underlying factual questions." Amgen Inc. v. Amneal Pharm. LLC , 945 F.3d 1368, 1375 (Fed. Cir. 2020) (citing Teva Pharm. USA, Inc. v. Sandoz, Inc. , 574 U.S. 318, 332, 135 S.Ct. 831, 190 L.Ed.2d 719 (2015) ). Where, as here, the lower tribunal's construction is based solely on evidence intrinsic to the patent, we review the construction de novo . Shire Dev., LLC v. Watson Pharm., Inc. , 787 F.3d 1359, 1364 (Fed. Cir. 2015) (citing Teva , 574 U.S. at 330–33, 135 S.Ct. 831 ).

Firebug argues that the Board erred in determining that the preamble of claim 1 of each of the Firebug patents, which recites "[a]n internally illuminated textile footwear comprises," does not limit the claims. Specifically, Firebug argues that the preamble limits the scope of the claims to "textile footwear." According to Firebug, when the preamble's requirement of textile footwear is read together with the claims’ limitation that the upper is light diffusing, the claims necessarily require that the light diffusing portion of the upper—that is, the portion of the outermost layer of the footwear that is illuminated—be textile. Firebug argues that neither Parker nor Rosko disclose internally illuminated footwear having a textile light diffusing layer and therefore the references do not render the claims obvious.

Stride Rite responds that the preambles do not limit any of the challenged claims because the bodies of the claims recite structurally complete articles, and the preamble merely states an intended use of the claimed structure. However, according to Stride Rite, even if the preambles do limit the claims to require textile footwear, the Board's claim construction error was harmless because the Board alternatively found that the prior art discloses footwear with a textile upper, and that finding is supported by substantial evidence.

Whether a claim preamble is considered to be a limiting part of the claim matters, inter alia, because, if it is not, the scope of the claim is broader, but the claim is vulnerable to more potentially-invalidating prior art. Here, we agree with Firebug that the preamble of claim 1 of the ’574 patent is limiting but conclude that the preamble of claim 1 of the ’038 patent is not. However, we agree with Stride Rite that even though the preamble is limiting with respect to the challenged claims of the...